This is a long one

[H.R. Paperstacks]

I can't get the right answer and I suspect its because of the length and hidden mistake

Let X and Y be randon variables such that X has density function

f(x)= 3x^2 for 0<x<1

and the conditional density of Y given X=x0 is

g(y|x0) = ky/x0^2 for 0<y<5x0

Then over the appropriate domain the conditional density of X given Y=y0 is

the answer is 5/(5-y0)

But I can't get that

[mjlee08]

I tried this and it seemed to work...

Find f(x,y) by multiplying g(y|x)f(x) = f(x,y). Then, integrate that in terms of x to get f(y). Your bounds will be from (1/5)y to 1. So f(x|y)=f(x,y)/f(y) and you should get 5/(5-y).